Lock



July 19, 1938.

D. s. GElsER LOCK Filed March 13, 1936 man Hilf S l l all Patented July19, 1938 FATE 'l' FFECE LOCK Daniel S. Geiser, Waynesboro, Pa.

Application March 13, 1936, Serial No. 68,729

12 Claims.

One of the important objects of the present invention is to provide anovel and eifective means for controlling the character of the key to beinserted in the lock, said means being readily a1- terable in order toaccommodate various forms of keys of the general type and excludeimproper keys.

A further object is to provide novel key operated means that willrequire the service of a particular type of key that can be inserted inthe above mechanism, and which operates through frictional contact,thereby making it practically impossible to pick the lock, or in otherwords surreptitiously operate it by means other than the authorized key.

The invention may be applied to any form of key operated lock.

One embodiment of the invention in which the device is shown applied toa door knob is illustrated in the accompanying drawing, wherein:

Figure 1 is a sectional view through a portion of a door in which theembodiment of the invention is installed.

Figure 2 is a cross sectional view on the line 2-2 of Figure l, andshowing the locking mechanism in its effective relation with respect tothe operating knob.

Figure 3 is a view similar to Figure 2, but showing the lockingmechanism coupling the knob to the latch bolt operating means.

Figure 4 is an end elevation of the key-receiving knob.

Figure 5 is a detail sectional view on the line 5 5 of Figure 1.

Figure 6 is a detail perspective view with the sections of the key guardseparated.

Figure '7 is a detail sectional view through the coupling plunger.

Figure 8 is a sectional view on the line 8-8 of Figure '1.

Figure 9 is an end elevation of the plunger operating cam device.

Figure 10 is a side elevation of the same.

Figure 1l. is a View of the other end of said cam device to that shownin Figure 9.

Figure l2 is a perspective view of a key for use with the device.

A horizontal sectional portion of a door .is shown at i2, the same beingmortised to receive a reciprccatory latch bolt I 3. Extending across thedoor is a knob spindle It having the usual cam or other device I5 foroperating the latch. One end of this spindle projects from one side ofthe door and has iixed thereto the usual knob IG by which the spindlecan be turned, to operate the latch bolt in a well-known manner.

Mounted on the side of the door opposite to that from which the knob I6projects, is an escutcheon plate I'I carrying an outstanding sleeve I 3that provides a shield as hereinafter explained. The end of the spindleI4 projects into the shield and is provided with a head I9. An outerknob is provided with a tubular shank 2| that is rotatable within theshield sleeve i8 and around the head I9, the same being secured in placeby a holding washer 22 mounted on its inner end and located behind theinner end of the sleeve I8.

The head I9 and consequently `the spindle Ill is adapted to be coupledto the knob shank 2| in order that the spindle and consequently thelatch bolt I3 can be operated. For this purpose the said head I9 has atransverse socket 23 in which is a transversely reciprocatory couplingplunger 24 whose outer end is adapted to move into and out of one of aset of openings 25 formed in the tubular shank 2|. When the plunger 24'is out of such engagement, or as shown in Figures 1 and 2, the knob 20is free to rotate and can have no effect on the spindle M. When theplunger 24 is in one of the openings 25, or as shown yin Figure 3, itWill be obvious that when the knob 20 is turned, the head I9 and thespindle Hl will be rotated, thereby actuating the latch bolt.

The plunger 24 is operated by a cam piece 26 located longitudinally inthe head i9 and rotating on the axis thereof. 'Ihis cam piece has arounded face 2l and a flat face 28 adapted to respectively bear againsta follower 29 slidably mounted in a socket 3B of the plunger, saidfollower in turn operating against a spring 3| that bears against theend of the plunger. If the cam piece is turned so that the follower 29rests against the flat side 28 of the cam piece 26, or as shown inFigures 1 and 2, the plunger will be in its inactive position and thespring bearing against the flat face, will hold the cam againstrotation. If, however, the cam piece is rotated, so that the roundedface 27 bears against the follower 29, or as shown in Figure 3, thenthrough the intermediate spring 3| the plunger will be forced outwardly,so that if the knob is turned until one of the openings 25 registerswith said plunger, it will snap into the opening. The knob Will bethereby locked to the head I9 and if the knob is now turned, it Willturn the spindle S4 and actuate the latch bolt. It will be notedincidentally that these parts are entirely housed within the shieldsleeve I3 of the escutcheon plate.

The cam piece 26, it will be noted, extends transversely through theplunger and has bearings on opposite sides of the same in the head I9.When the plunger is retracted the follower 29 rests upon the flat side26 of the cam piece. When the plunger is projected and is borne againstby the rounded side of the cam piece 26, the flat side thereof bearsagainst the flat ends 24a of the openings and thus there is no tendencyof the cam piece to accidentally turn. The cam piece 26 in turn iskey-operated and for that purpose it has at its outer end a head 32which is preferably provided with an outwardly opening .and inwardlytapered socket 33 whose side Walls are smooth.

The key preferably employed is shown at 34, and includes a shank 35 thatis twisted or substantially of screw shape. The twisted shank of the keymay be provided with scores 35o. The inner end or bit 36 of this key istapered, the taper corresponding substantially to the taper of thesocket 33 so that the edges of the bit will frictionally bear againstthe side walls of the socket. By forcing the key in, therefore, .asufficient frictional grip will be obtained between the key and the headso that the cam piece 25 can be turned either tol project the plunger orto permit its withdrawal. The provision of a rounded socket allows theentrance of a key in any position instead of requiring it to be in adefinite position with respect to the head 32 and also accommodates thetwisted end of a spiral key.

In order to insure that the lock will only be operable by apredetermined authorized key, a guard is placed in the tubular shank ofthe knob 20 between the keyhole 31 of said knob and the head 32 of thecam piece 21. 'I'his guard consists of detachably telescoped tubularsections 38 and 39, each having an end wall provided with a passagewayin the form of slots 40 and 4l. The key guards are relatively rotatable,that is to say, when separated as shown in Figure 6, the position of onewith relation to the other can be changed and the sections againintertted. In order to hold them against relativ-e rotation whenintertted, any suitable means may be employed, but in the structureshown the exterior wall of the section 39 is provided with ribs 42 andthe internal wall of the other section 38 has grooves 43 that receivethe same. It will be evident therefore that by changing the relation ofthe sections the relative angularity of the two passageways or slots 40and 4l can be altered and consequently the pitch of the twisted keyshank that can pass through the two passages. The same effect may beobtained by changing the distance between the end walls of thetelescoped sections. By placing them farther apart or closer together,the pitch of the key that can pass through both passages is changed. Inorder to accurately and positively space the two walls, washers 4la maybe inserted within the outer tubular section 38 and between its end walland the inner end of the inner section 39. Thus any one of a. set ofkeys having shanks provided with different degrees of pitch can be madeto become operable by either of the adjustments while others areexcluded. The guard as a whole it will be understood is rotatable withinthe knob shank 2| and there is preferably interposed between the rearend of the guard and the front end of the head 32 an antifriction washer44.

The side of the key passages 40 and 4l of the guard sections areprovided with suitable projections 45 to cooperate with the scores 35aof the key shank to exclude improperly scored keys and further safeguardthe lock against operation by unauthorized keys,

The lock functions as follows. When the coupling plunger 24 is in itsretracted and inactive relation, the latch bolt I3 can only be operatedby the inner knob I6, the outer knob being freely rotatable withouteffecting any operation of the lock. With this structure it will benoted particularly by reference to Figure 5 that the eX- posed openingto the interior of the lock through the slots 40 and 4l is very small,being merely the intersecting portions of the slots. Moreover thekey-receiving socket of the cam piece having smooth walls, leavesnothing to be engaged by any unauthorized device that may be passedthrough the keyhole and engaged with the socket piece. The danger ofeffectively tampering with the lock is thus reduced to a minimum.

When the proper key is inserted, it will obviously pass through th-eslots 40 and 4l and slightly turn the guard until the inner end or bitof the key is frictionally engaged with the walls of the socket. When soengaged approximately a one-half turn to right or left of the key willpositively rotate the cam piece, thus forcing out the plunger and asalready explained, coupling the outer knob 2li to the spindle.Consequently when said knob is turn-ed the latch bolt will be withdrawn.If an attempt is made to use a key having a pitch different from that ofthe proper key, it will be evident that it cannot enter because therelation of the slots 4) and 4I will prevent its passage.

It will be readily appreciated that any form of rotatable lock operatingmechanism may be substituted for the cam piece, and that this device maytherefore be applied to any form of key operated lock.

From the foregoing, it is thought that the construction, operation andmany advantages of the herein described invention will be apparent tothose skilled in the art without further description, and it will beunderstood that various changes in the size, shape, proportion and minordetails of construction may be resorted to without departing from thespirit or sacrificing any of the advantages of the invention.

What I claim is:

l. In a lock for operation by a screw-like key, the combination with akey-receiving casing, of a key guard comprising sections havingpassageways for the shank of the key, said sections being relativelyadjustable to vary the relative position of the passageways and therebygovern the character of the key shank that can be effectively engagedtherein.

2. In a lock for operation by a screw-like key, the combination with akey receiving casing, of a key guard comprising sections havingpassageways for the shank ofthe key, said sections being relativelyadjustable to vary the relative position of the passageways and therebygovern the character of the key shank that can be engaged therein, andmeans for securing the sections against relative movement and indifferent adjusted positions.

3. In a lock for operation by a screw-like key, the combination with akey-receiving casing, of a key guard comprising telescoped sectionshaving passageways for the shank of the key, said sections beingrelatively angularly adjustable to vary the relative position of thepassageways and thereby govern the character of the key shank that canbe engaged therein, and a plurality of ribs in the meeting surfaces of.the sections for securing the sections against relative rotation and indifferent adjusted positions.

4. In a lock for operation by a screw-like key, the combination with akey-receiving casing, of a key guard comprising sections havingpassageways in which the screw-like portions of the key shank cansimultaneously be engaged, said sections being relatively angularlyadjustable to vary the relative positions relation of the passagewaysand thereby change their pitch and govern the pitch of the key shankthat can be engaged therein, and means for securing the sections, intheir adjusted relative positions.

5. In a lock for operation by a screw-like key, the combination v/ith akey-receiving casing, of a key guard comprising detachably interfittingangularly adjustable sections having interlocking portions and eachsection having a passageway for the key shank and said passageways beingbrought into different relative positions when the sections arerelatively rotated and interlocked in different positions to control thecharacter of the pitch of the key shank that can be eiectively engagedtherein.

6. In a lock for operation by a screw-like key, the combination With acasing having a key entrance opening and a device therein to be operatedby the key, of a key guard interposed between. the entrance and thedevice and comprising angularly adjustable intertted sections havingpassageways through which the screwlike shank of the key passes, saidsections being relatively rotatable to change the relative positions ofthe passageways and thus vary their pitch and the consequent pitch ofthe key shank that will pass therethrough, and a plurality of flutes inthe meeting face of the interitted sections for securing the shanksagainst relative rotation and in different adjusted relations andwhereby a multiplicity of different adjustments may be made.

7. In a lock for operation by a screw-like key, the combination with akey-receiving casing, of a key guard comprising spaced Walls, the Wallshaving slot-like passageways arranged in relatively angular relation forthe shank of. the key, and the distance between the Walls beingadjustable to vary the relative positions of the passageways and therebygovern the character of the key shank that can be engaged therein.

8. In a lock for operation by a screw-like key, the combination with akey-receiving casing, of a key guard comprising adjustably telescopingsections, each section having an end Wall spaced from the end wall ofthe other section, and the end walls having slot-like passages inrelatively angular relation for the screw-like shank of the key, andmeans for securing the sections in adjusted positions whereby the pitchof the key shank that will pass through the passageways is controlled.

9. In a lock, the combination with a latch bolt and spindle foroperating the same, of a knob freely rotatable with respect to thespindle and having a chambered shank, a coupler for connecting the knoband spindle, and a rotatableY device for operating the coupler andhaving a tapered substantially smooth walled socket for frictionalengagementby the tapered end of a key and operable by such frictionalengagement.

10. In a lock including a latch bolt and a spindle for operating thesame, the said spindle having a transverse bore and a knob freelyrotatable with respect to the spindle and having a chambered shanksurrounding the spindle, a coupler movable from an inoperative positionwithin the bore of the head to an extended position in engagement withthe knob shank for connecting the spindle and knob, and a rotatable camfor moving the coupler having means for engagement and operation by akey.

11. In a lock, the combination with a latch bolt, of a rotatable spindlefor operating it having a head, a rotatable knob having a tubular shankrotatable about the head, a transverse plunger in the head movable intoand out of engagement with the knoby shank to couple the two, a camrotatably mounted in the head and engaging the plunger to actuate it, asubstantially smooth Walled socket piece carried by the cam, andkey-receiving mechanism in the knob including a guard interposed betweenthe end of the knob and said socket piece, and comprising angularlyadjustable sections having passageways that can be set in diierentangular relations to permit the passage o1 the screw-like shank of a keyhaving a certain corresponding pitch and preventing the passage of.those of other pitches and giving access of the proper key to the socketpiece of the cam.

12. In a lock including a latch bolt, a spindle for operating the latchbolt, the said spindle having a head provided with a transverse bore, aknob having a tubular shank rotatably surrounding the head of thespindle and having a series of spaced sockets for registering with thebore, a coupler slidably mounted within the bore of the head forcoupling the knob shank and head, a rotary cam mounted in the head formoving the coupler into and out of engagement with the sockets of theknob shank, and a spring interposed between the cam and the coupler.

DANIEL S. GEISER.

